The present application is directed to washers used in mechanical structures, and particularly to washers that can be inserted in an existing mechanical structure without disassembly of that structure.
Often mechanical structures and equipment that include coupled elements, which are designed for some relative movement and have been used for some time, develop an undesirable wobble or play between the coupled elements. This wobble or play can often be reduced to an acceptable level or even eliminated by the insertion of a washer of suitable thickness between the two coupled elements. It is most desirable if the washer can be inserted without disassembling the mechanical structure.
One such washer disclosed in U.S. Pat. No. 1,558,364 is formed of two semi-cylindrical sections of identical construction. Each section includes a tongue on one end that terminates in a circular head portion having a beveled edge. The other end of each section includes a socket or recess shaped to conform to the configuration of the tongue and head including a V-shaped groove to accommodate the beveled edge of the circular head portion. While a washer can be constructed in accordance with this design when unrestricted by any other mechanical structures, the insertion of two such sections between two wobbling coupled elements becomes problematic particularly if the internal radius of the two semi-cylindrical sections closely approximates the outside radius of any coupling between the coupled elements of the mechanical structure. Further the retention of the two sections of the washer together relies on the malleability of the material forming the washer sections.
Another such washer disclosed in U.S. Pat. No. 5,106,252 is also formed of two semi-cylindrical sections of identical construction. One end of each semi-cylindrical section includes a projecting tongue while the other end includes a pair of leaves defining a slot adapted to receive a projecting tongue of the adjacent semi-cylindrical section. In one embodiment the tongue includes a centrally located depression while one of the leaves includes a centrally located projection sized and located to fit in the depression. In another embodiment the tongue includes a centrally located projection while one of the leaves includes a centrally located depression sized and located to receive the projection on the tongue. In all embodiments, the two semi-cylindrical sections of the washer are retained together by the conjunction of the projections and depressions on the tongues and slot-defining leaves. To achieve assembly of such a construction, however, the two leaves of each slot must be spread apart by a distance sufficient to let the projection squeeze past an un-depressed portion of the washer until the locking position is achieved. While a washer can be constructed in accordance with this design when unrestricted by any other mechanical structures, the insertion of two such sections into a space between two wobbling coupled structures becomes problematic. This temporary spreading of the two leaves requires that the size of the space into which the washer is being assembled must be greater than the thickness of the washer once assembled, thus leaving room for wobble and play to continue.
Other washers are disclosed in U.S. Pat. Nos. 1,332,626 and 6,488,461 that have connecting features on the ends of the two sections of such design that the size of the space between the two wobbling coupled structures must be at least twice the thickness of the washer once assembled, thus leaving even more room for wobble and play to continue. What is needed is a washer that is capable of insertion in a space between two wobbling coupled structures, the washer being of the same thickness as the space between the coupled structures, to remove all play between the coupled structures.